1. Field of the Invention
The present invention concerns a ski which is intended to glide on the snow and ice. Such a ski can be used especially for alpine skiing.
The invention also concerns more generally, any board intended to glide on the snow, such as a snowboard or a monoski, for example.
2. Discussion of Background and Material Information
Currently known skis of the aforementioned type are generally in the shape of an elongated beam, whose front end is turned up to form the shovel. They comprise a bottom gliding surface, or sole, as well as a top surface. These two surfaces are connected to one another by two lateral edges or side surfaces. The usually metallic running or bottom edges are further located at the junction between the lateral edges and the bottom surface. Usually, the binding elements are assembled at the top surface of the ski, in its central zone.
Present day skis are obtained according to one or the other of two conventional composite structures, a sandwich structure or a box structure.
A ski having a sandwich structure is described in French Patent Publication No. 1,124,600 (FIGS. 1 and 2), for example. Such a ski has a central core which is obtained in a fibrous or alveolar material, for example. The core is covered on the top and bottom by upper and lower reinforcement layers or walls.
It is known that the sandwich structure skis are well adapted to various conditions of use, whose operation is easy and forgiving. However, such skis have the disadvantage of not possessing high lateral gripping qualities in the turns and on inclines.
A box structure ski is described especially in French Patent Publication No. 1,124,600 (FIG. 3). Such a ski has a core which can be made of fibrous or alveolar material. The core is covered on its top, bottom and lateral surfaces by reinforcement layers or walls which constitute a box.
Such a structure provides the ski with greater torsional rigidity. Compared with a sandwich structure ski, such a ski has higher gripping qualities. However, such skis are not as easy and forgiving in operation as the sandwich structure skis. Such box structure skis are not the best adapted to skiers with little experience.
A box structure ski is also known from the French Patent Publication No. 2,611,517, whose thickness towards the ends is less than in the middle sole zone, and whose edge inclination, with respect to a horizontal plane, is lesser towards the ends and greater in the middle sole zone. These shape characteristics tend to provide the ski with greater torsional rigidity in the central zone, and greater flexibility towards the ends of the ski. Such a ski possesses very good gripping qualities. However, it has a box structure along its entire length, and for this reason it is not optimally adapted to inexperienced skiers, because its operation requires a certain mastery on the skier's part.